I am having a problem with the MIFI 6620L device. Frequently, a laptop connected to the device will stop getting internet access. Other devices will maintain their connection, and I can add more to the mifi during this time. This is happening will multiple laptops and multiple mifi devices. If I ask windows to repair the connection, it is usually successful, giving a message that the default gateway couldn't be found, and that it repaired that problem. I have tried so many things trying to get around this. One thing I recently did that ended up having an odd outcome was this: I set the ip address on the laptop as a static, and successfully connected and was browsing around the internet. About 10-15 minutes later, the connection was limited. The mifi still showed the laptop as being connected, but I could not reach the mifi webpage to check its settings. I connected with another laptop, and looked at the connected devices there. It said that the other laptop was now unknown, and it was trying to assign it the first dynamic ip address in its range, instead of showing the ip address I had assigned to it, and successfully connected with. I'm at a loss with this issue, because the issue comes up again if I use another laptop. Also, if I put the first laptop on another mifi, it comes up there, too.
If the problem is happening with the same laptop and multiple Jetpacks then there might be an issue with that particular laptop.
If the problem is happening with multiple laptops on the same Jetpack then it might be something with the Jetpack that Verizon can help you with. Most likely starting with the basic resets and then evaluating your options for replacement under the warranty followed by upgrades or new devices all together.
When multiple laptops have problems with multiple jetpacks then there is likely something else funky going on in that particular environment like interference from neighboring devices or other appliances in the home.
Based on what you have shared so far it sounds like the laptops are physically disconnecting from the Jetpack when the problem happens. The laptops may believe they are still connected but the default gateway cannot be accessed and the Jetpack cannot speak to them either. Refreshing the connection brings everything back temporarily until the event comes along to knock it out again.
One thing you could confirm is to look up the IP address of the laptop the next time this happens. On windows machines this is an IPConfig /All command. It will show you your current IP and default gateway along with some other info. Compare this to when the connection is working normally. If you are receiving a 169.254.x.x IP then your laptop is no longer connected to the Jetpack.
I too am having a similar issue. My disconnects are not related to laptops, but to items like my wireless smoke detectors, wireless printer, wireless on demand TV box, and wireless thermostats. As they sit idle they will disconnect from the MIFI and drop off line. - 6240L shows them no longer connected. I have to restart each unit to reconnect, but then after a while they get disconnected.
I have set the Jetpack to Never Sleep and Never turn off, but that hasn't made a difference.
My older 890L didn't have this problem with any of these issues.